In an industrial or other work environment where noise is a problem it is common to provide workers with a pair of ear defenders which consist of large sound dampening ear pieces supported from the top of the head by a strap. If a user of such a device wears glasses or wishes to wear safety glasses then the only option is to break the seal of the ear pieces around the ear and insert the stems of the glasses over the user's ear, thereby offsetting the beneficial effects of the ear defenders. One of the problems in attaching safety glasses or any other glasses for that matter to a pair of ear defenders is the variability of positioning relative to the eyes of different users. Adjustments to both the length and the vertical positioning are required to properly position the lenses.
U.S. Pat. No. 264,574 issued to Shone discloses a set of spectacles mounted on the underside of a hat rim and suspended from hooks. Other than moving the hooks there is no adjustment shown. U.S. Pat. No. 4,129,362 issued to Lorenzo discloses an eyeglass structure having a pivot connection on the temple pieces proximate the ears and a tilt adjustment of the lenses by a pivotal keeper and a notched region on the temple arm for engagement by the keeper. There is nothing to restrain the temple arm portion from pivoting except apparently friction. Moreover, the course tilting adjustment is accomplished by a pawl which is not biased into engagement with the notched region. Consequently, it is not known how the pawl can stay reliably engaged with the notched region. In any event tilting adjustments done close to the lenses change the angle of the shield or glass significantly unlike such adjustments done further back along the temple arms.
Accordingly, it is an object of the invention to provide a set of eyeglasses or safety glasses which are capable of being mounted on a pair of ear defenders. A further object is to provide a set of such glasses which are adjustable not only in distance away from a face of a user but also in vertical position.